Early Pleistocene

The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest (or lowest) division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time between 2.580 ± 0.005 Ma (million years ago) and 0.773 ± 0.005 Ma. The term Early Pleistocene applies to both the Gelasian Age (to 1.800 ± 0.005 Ma) and the Calabrian Age.[1]

Subdivisions of the Quaternary System
System/
Period		 Series/
Epoch		 Stage/
Age		 Age (Ma)
Quaternary Holocene Meghalayan 0 0.0042
Northgrippian 0.0042 0.0082
Greenlandian 0.0082 0.0117
Pleistocene 'Upper' 0.0117 0.129
Chibanian or 'Middle' 0.129 0.774
Calabrian 0.774 1.80
Gelasian 1.80 2.58
Neogene Pliocene Piacenzian 2.58 3.60
Notes and references[1][2]
Subdivision of the Quaternary Period according to the ICS, as of May 2019.[1]

For the Holocene, dates are relative to the year 2000 (e.g. Greenlandian began 11,700 years before 2000). For the beginning of the Northgrippian a date of 8,236 years before 2000 has been set.[2] The Meghalayan has been set to begin 4,250 years before 2000.[1]

'Tarantian' is an informal, unofficial name proposed for a stage/age to replace the equally informal, unofficial 'Upper Pleistocene' subseries/subepoch.

In Europe and North America, the Holocene is subdivided into Preboreal, Boreal, Atlantic, Subboreal, and Subatlantic stages of the Blytt–Sernander time scale. There are many regional subdivisions for the Upper or Late Pleistocene; usually these represent locally recognized cold (glacial) and warm (interglacial) periods. The last glacial period ends with the cold Younger Dryas substage.

While the Gelasian and the Calabrian have officially been defined by the International Union of Geological Sciences (IUGS) to effectively constitute the Early Pleistocene, the succeeding Chibanian and Tarantian ages have yet to be ratified.[3] These proposed ages are unofficially termed the Middle Pleistocene and Late Pleistocene respectively. The Chibanian provisionally spans time from 773 ka to 126 ka, and the Tarantian from then until the definitive end of the whole Pleistocene, c. 9700 BC in the 10th millennium BC.[1]

Notes
  1. Cohen, K. M.; Finney, S. C.; Gibbard, P. L.; Fan, J.-X. (January 2020). "International Chronostratigraphic Chart" (PDF). International Commission on Stratigraphy. Retrieved 23 February 2020.
  2. Mike Walker; et al. (December 2018). "Formal ratification of the subdivision of the Holocene Series/Epoch (Quaternary System/Period)" (PDF). Episodes. Subcommission on Quaternary Stratigraphy (SQS). 41 (4): 213–223. doi:10.18814/epiiugs/2018/018016. Retrieved 11 November 2019. This proposal on behalf of the SQS has been approved by the International Commission on Stratigraphy (ICS) and formally ratified by the Executive Committee of the International Union of Geological Sciences (IUGS).
  3. P. L. Gibbard (17 April 2015). "The Quaternary System/Period and its major sub-divisions". ScienceDirect. Elsevier BV. pp. 686–688. Retrieved 13 November 2019.


gollark: That should implement Copy, so just dereference it.
gollark: There's an option method to convert Option<&T> to &Option<T>, yes?
gollark: I assume that this might be using the ESP8266's weird I2S hardware, assuming it has similar stuff to the ESP32.
gollark: https://duino4projects.com/esp8266-i2s-software-based-10-base-t-ethernet-driver/
gollark: The cable allows 100MHz without beeing things, but it is itself *just a cable*.
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